Minecarts stop moving when hitting a redstone block, even if it has powered rails next to it. Only seems to happen with redstone blocks. replacing the blocks with regular blocks with a lever lets them bounce off. This happens the same way underwater.

How to replicate: make a line of rails between 2 redstone blocks with a powered rail on each side

What should happen: When the minecart reaches the end it should "bounce" off the block with the powered rail

What happens: The minecart stops when it reaches the end